[GL] Add assertions in GeoLib::Triangle ctor.

GeoLib/Triangle.cpp

@@ -24,6 +24,7 @@ namespace GeoLib {
 Triangle::Triangle (std::vector<Point *> const &pnt_vec) :
 	_pnts(pnt_vec), _initialized (false), _longest_edge (0.0)
 {
+	assert(!_pnts.empty());
 	_pnt_ids[0] = std::numeric_limits<std::size_t>::max();
 	_pnt_ids[1] = std::numeric_limits<std::size_t>::max();
 	_pnt_ids[2] = std::numeric_limits<std::size_t>::max();
@@ -33,6 +34,7 @@ Triangle::Triangle (std::vector<Point *> const &pnt_vec,
 	std::size_t pnt_a, std::size_t pnt_b, std::size_t pnt_c) :
 	_pnts(pnt_vec), _initialized (true), _longest_edge (0.0)
 {
+	assert(!_pnts.empty());
 	_pnt_ids[0] = pnt_a;
 	_pnt_ids[1] = pnt_b;
 	_pnt_ids[2] = pnt_c;